Field trial of cyfluthrin as an effective and safe insecticide for control of malaria vectors in triple insecticide resistant areas

Cyfluthrin (Solfac**) 10 wp, a synthetic pyrethroid was evaluated for its efficacy in malaria control through primary health centre approach, and for its acceptance by the community and effect on human health, and non target organisms, in predominantly tribal areas of Maharashtra and Gujarat from 1988 to 1990. Two dosage schedules; 2 rounds of indoor residual sparying a year, at 25 mg/sq. m2 in Maharashtra, and 3 rounds a year at 15 mg/sq. m2, in Gujarat were followed. There was significant reduction in per man hour densities of An. culicifacies the principal malaria vector, and collaterally of C. quinquefasciatus also. Significant reductions in slide positivity rates and slide falciparum rates were observed in both the areas as compared to the controls. The community acceptance of Cyfluthrin in terms of room coverage was 96% in Gujarat, and 89% in Maharashtra, as against average 68.5% and 55% in case of DDT and Malathion respectively. There were no reported ill-effects on humans or non-target organisms.     

Identification of Drosophila cytoskeletal proteins by induction of abnormal cell shape in fission yeast

To clone metazoan genes encoding regulators of cell shape, we have developed a functional assay for proteins that affect the morphology of a simple organism, the fission yeast Schizosaccharomyces pombe. A Drosophila melanogaster cDNA library was constructed in an inducible expression vector and transformed into S. pombe. When expression of the Drosophila sequences was induced, aberrant cell shapes were found in 0.2% of the transformed colonies. Four severe phenotypes representing defects in cytokinesis and/or cell shape maintenance were examined further. Each displayed drastic and specific reorganizations of the actin cytoskeleton. Three of the cDNAs responsible for these defects appear to encode cytoskeletal components: the actin binding proteins profilin and cofilin/actin depolymerizing factor and a membrane-cytoskeleton linker of the ezrin/merlin family. These results demonstrate that a yeast phenotypic screen efficiently identifies conserved genes from more complex organisms and sheds light on their potential in vivo functions.     

The Tarasoff raid: a new extension of the duty to protect

The authors discuss the general outlines of the Tarasoff duty of psychotherapists to protect potential victims of their violent patients. They describe the flexible range of clinical responses that therapists have utilized, as well as their professional concerns about preserving patient confidentiality (or at least strictly circumscribing the scope of disclosure when confidentiality must be breached). A recent case is reported that illustrates a striking new extension of Tarasoff, involving a police search and seizure of a psychotherapist's confidential treatment records and tapes, in response to a third-party complaint that the records contained evidence of his patients' violent acts and propensities. The implications of this case are that the therapist's discretion in the assessment of his duty to protect, the selection of a proper course of action, and the implementation of specific responses may be taken out of his hands, for all intents and purposes, and expropriated by law and order officials. Moreover, regardless of whatever clinical approach he adopts and whether or not he issues a warning, his attempts to preserve patient confidentiality are bound to prove unsuccessful in any future legal proceedings. Patient communications are likely to lose their confidential status on the grounds that they caused or triggered the Tarasoff warning (or that they should have triggered it). If the patient directed serious threats against the therapist himself, the court may find that, as a consequence, a "genuine therapeutic relationship" ceased to exist and thereafter all patient disclosures were no longer confidential on that basis.(ABSTRACT TRUNCATED AT 250 WORDS)     

An implantable centrifugal blood pump for long term circulatory support

A compact centrifugal blood pump was developed as an implantable left ventricular assist system. The impeller diameter is 40 mm and the pump dimensions are 55 x 64 mm. This first prototype was fabricated from titanium alloy, resulting in a pump weight of 400 g including a brushless DC motor. Weight of the second prototype pump was reduced to 280 g. The entire blood contacting surface is coated with diamond like carbon to improve blood compatibility. Flow rates of over 7 L/min against 100 mmHg pressure at 2,500 rpm with 9 W total power consumption have been measured. A newly designed mechanical seal with a recirculating purge system ("Cool-Seal") is used as a shaft seal. In this seal system, seal temperature is kept under 40 degrees C to prevent heat denaturation of blood proteins. Purge fluid also cools the pump motor coil and journal bearing. The purge fluid is continuously purified and sterilized by an ultrafiltration filter incorporated into the paracorporeal drive console. In vitro experiments with bovine blood demonstrated an acceptably low hemolysis rate (normalized index of hemolysis = 0.005 +/- 0.002 g/100 L). In vivo experiments are currently ongoing using calves. Via left thoracotomy, left ventricular apex-descending aorta bypass was performed utilizing a PTFE (Polytetrafluoroethylene) vascular graft, with the pump placed in the left thoracic cavity. In two in vivo experiments, pump flow rate was maintained at 5-8 L/min, and pump power consumption remained stable at 9-10 W. All plasma free hemoglobin levels were measured at < 15 mg/dl. The seal system has demonstrated good seal capability with negligible purge fluid consumption (< 0.5 ml/ day). Both animals remain under observation after 162 and 91 days of continuous pump function.     

Wheelchair stability: effect of body position

When a wheelchair user reaches and leans, the static stability decreases in the direction of the lean and increases in the opposite direction. The purpose of this study was to determine the extent of this effect. We studied 21 nondisabled subjects in a representative wheelchair, measuring the static forward, rear, and lateral stability on a tilting platform. Reaching and leaning away from the tip added stability, with mean increases ranging from 9.1% to 124.3% of the neutral-position values, whereas reaching and leaning toward the tip reduced stability, with mean decreases ranging from 25.2% to 52.3% (p < 0.0001). The stability range ("away" minus "toward") varied from 52.4% to 149.5%. Reaching forward had a greater effect on stability than did reaching back or to the side. Wheelchair users with the ability to control their body positions can profoundly affect the stability of their wheelchairs, a factor that should be considered in wheelchair selection and training.     

Policies, practices, and attitudes of North American medical journal editors

OBJECTIVE: To describe U.S. and Canadian medical journals, their editors, and policies that affect the dissemination of medical information. DESIGN: Mailed survey. PARTICIPANTS: Senior editors of all 269 leading medical journals published at least quarterly in the United States and Canada, of whom 221 (82%) responded. MAIN MEASURES: The questionnaire asked about characteristics of journal editors and their journals and about journals' policies toward peer review, conflicts of interest, prepublication discussions with the press, and pharmaceutical advertisements. RESULTS: The editors were overwhelmingly men (96%), middle-aged (mean age 61 years), and trained as physicians (82%). Although 98% claimed that their journals were "peer-reviewed," the editors differed in how they defined a "peer" and in the number of peers they deemed optimal for review. Sixty-three percent thought journals should check on reviewers' potential conflicts of interest, but only a minority supported masking authors' names and affiliations (46%), checking reviewers' financial conflicts of interest (40%), or revealing reviewers' names to authors (8%). The respondents advocated discussion of scientific findings with the press (84%), but only in accord with the Ingelfinger rule, i.e., after publication of the article (77%). Fifty-seven percent of the editors agreed that journals have a responsibility to ensure the truthfulness of pharmaceutical advertisements, and 40% favored subjecting advertisements to the same rigorous peer review as scientific articles. CONCLUSIONS: The responding editors were relatively homogeneous demographically and professionally, and they tended to support the editorial status quo. There was little sentiment in favor of tampering with the current peer-review system (however defined) or the Ingelfinger rule, but a surprisingly large percentage of the respondents favored more stringent review of drug advertisements.     

Treatment orientation and associated characteristics of North American academic psychiatrists

We present data showing the degree to which a "biological-psychotherapeutic" division persists in American psychiatry, and how psychiatrists' treatment orientation is associated with personal and professional characteristics. Almost two thirds of academic psychiatrists who responded to our survey (N = 435) could be classified as either biological (27%) or psychotherapeutic (37%) in orientation, according to the proportion of their caseload to which they provided psychotherapy (< or = 25% vs. > 75%). There appears to have been an increase over the last 35 years in the proportion of psychiatrists who can be classified as biologically oriented and a decrease in the proportion who can be classified as psychotherapeutically oriented, as well as the emergence of a large class of intermediate or "eclectic" practitioners (36%). Several personal and professional attributes were distributed differentially according to treatment orientation. Psychotherapeutically oriented respondents more frequently reported personal histories of psychiatric disorders than did biologically oriented respondents (64% vs. 39%) as well as greater satisfaction with clinical work (81% vs. 53% "very satisfied"). Differences were also found in age, gender, history of personal psychotherapy, family history of psychiatric disorder, history of marijuana use, degrees of involvement in research, teaching and clinical care of patients, and overall work satisfaction, as well as other characteristics.     

Reduction in enkephalin and substance P messenger RNA in the striatum of early grade Huntington's disease: a detailed cellular in situ hybridization study

The expression of enkephalin and substance P messenger RNAs was examined in the caudate-putamen of human post mortem tissue from control and Huntington's disease tissue using in situ hybridization techniques and human specific enkephalin and substance P [35S] oligonucleotides. Macroscopic and microscopic quantification of enkephalin and substance P gene expression was carried out using computer-assisted image analysis. Tissue was collected from six control cases with no sign of neurological disease and six Huntington's disease cases ranging from grades 0 to 3 as determined by neuropathological evaluation. The clinical and pathological diagnosis of Huntington's disease was confirmed unequivocally by genetic analysis of the CAG repeat length in both copies of IT15, the Huntington's disease gene. A marked reduction in both enkephalin and substance P messenger RNAs was detected in all regions of the caudate nucleus and putamen in Huntington's disease grades 2/3 when compared to controls; in the dorsal caudate few enkephalin or substance P messenger RNA-positive cells were detected. For the early grade (0/1) Huntington's disease cases, a heterogeneous reduction in both enkephalin and substance P messenger RNAs were noted; for enkephalin messenger RNA the striatal autoradiograms displayed a conspicuous patchy appearance. Detailed cellular analysis of the dorsal caudate revealed a striking reduction in the number of enkephalin and substance P messenger RNA-positive cells detected and in the intensity of hybridization signal/cell. These data suggest that both the "indirect" GABA/enkephalin and "direct" GABA/substance P pathways are perturbed very early in the course of the disease and that these early changes in chemical signalling may possibly underlie the onset of clinical symptoms.     

Intracellular fatty acid-binding proteins: putting lower vertebrates in perspective

Intracellular fatty acid-binding proteins (FABPs) are small (15 kDa), highly conserved cytoplasmic proteins that bind long-chain fatty acids and other hydrophobic ligands. Fifteen isoforms have been identified and characterized to date. Members of the FABP protein family share many common characteristics: they have a common "clamshell" tertiary structure despite significant variation in primary structure; they bind their ligands with 1:1 molar stoichiometry and micromolar affinity (with the exception of liver type FABP, which binds two fatty acids per FABP); they are ubiquitously expressed, yet are found at greatest concentration in tissues with high capacities to oxidize or store lipids; and their level of expression changes with conditions that affect overall lipid metabolism. Because of the ligands bound by FABP and FABP's tissue distribution, it is thought that FABPs play a role in the intracellular metabolism of lipids; however, a precise function(s) for FABP has not been defined. This review highlights contributions from researchers studying FABP in nonmammalian systems. FABPs isolated from birds, fish, amphibians, insects, and flatworms have similar structures to mammals in FABPs, yet they are expressed in systems with unique lipid metabolisms. Because mammals are closely related and have relatively invariant fatty acid metabolisms, non-mammals provide alternative systems that may reveal the elusive function(s) of this protein family.     

Polymerase chain reaction and other amplification techniques in mycobacteriology

Amplification methods for detection of Mycobacterium tuberculosis, such as polymerase chain reaction (PCR), have undergone much research and development in the last several years. The most common methods for extraction, amplification, and detection of mycobacterial nucleic acid sequences used in "in-house" PCR assays are discussed. A list of commercially prepared PCR and non-PCR amplification assays that should be available soon is included. The pros and cons of "in-house" versus commercial technology and issues of implementation of molecular technology in the clinical laboratory are reviewed.